High intensity discharge (HID) lamp starting apparatus

Abstract

Apparatus for starting and operating a high intensity discharge lamp includes a pair of terminals connectible to an AC service voltage source and coupled by a ballast to an HID lamp with a series connected gated switch and a non-linear dielectric element shunting the HID lamp, a series connected resistor and capacitor shunting the HID lamp and a bidirectional switch coupling the junction of the resistor and capacitor to the gate electrode of the gated switch whereby a delayed pulse of increased magnitude is applied to an HID lamp.

What is claimed is: 
     
       1. High Intensity Discharge (HID) lamp starting and operating apparatus comprising: an inductive ballast coupled to a high intensity discharge (HID) lamp;   terminal means coupled to said ballast and to said (HID) lamp and formed for connection to a service voltage source;   timing and triggering circuit means shunting said high intensity discharge (HID) lamp including a series connected resistor and capacitor shunting said lamp, a series connected gated switch and non-linear dielectric element shunting said lamp and a bidirectional switching means coupling the junction of said series connected resistor and capacitor to the gate electrode of said gated switch.   
     
     
       2. The apparatus of claim 1 wherein said non-linear dielectric element is in the form of a non-linear capacitor. 
     
     
       3. The apparatus of claim 1 wherein said non-linear dielectric element is in the form of a barium titanate device. 
     
     
       4. The apparatus of claim 1 wherein said gated switch is in the form of a silicon controlled rectifier and said bidirectional switching means is in the form of a diac. 
     
     
       5. The apparatus of claim 1 wherein said high intensity discharge lamp is in the form of an 85 watt high pressure sodium lamp and said non-linear dielectric element is in the form of a non-linear capacitor having a value of about 3.0 nanofarads. 
     
     
       6. Apparatus for starting and operating a high intensity discharge (HID) lamp comprising: terminal means formed for connection to a service voltage source;   ballast means coupled to one of said terminal means and to said HID lamp, said lamp coupled to the other one of said terminal means; and   timing and triggering circuit means shunting said high intensity discharge (HID) lamp, said circuit means including a series connected gated switch and non-linear capacitor shunting said (HID) lamp, a series connected impedance and capacitance in parallel connection with said series connected gated switch and non-linear capacitor, and a bidirectional switching means coupled to the junction of said series connected impedance and capacitance and to a gate electrode of said gated switch.   
     
     
       7. The apparatus of claim 6 wherein said non-linear capacitor is in the form of a barium titanate device. 
     
     
       8. The apparatus of claim 6 wherein said impedance is in the form of a resistor.